Traction device



June 15, W E MACK TRACTIN DEVICE Filed March 2, 1946 2 Sheets-Sheet 2 INVENTOR WyneE/MacK Patented June 15, 1948 UNITED vSTATES PATENT OFFICE TRACTION DEVICE Wayne lE. Mack, Martins Ferry, hio, assignor'to Wheeling Steel Corporation, 'Wheelng, y'W. Va., .a corporation 'of Delaware ./tmlication March 2, %46, Serial No. 651,487

4 Claims. (Cl. 23S-'14) This invention relates to traction devices, particularly Adevices for use in extricating yautomobiles and 'other 'vehicles which have become bogged down in mud or `which lare stuck in snow or ice so that lthe traction aiorded by normal operation -co the vehicle is insuilicient `to move it.

Many traction vdevices for the purpose above mentioned have 'heretofore 'been proposed, 'but none -of them, so far las 'I am aware, has proved enti-rely satisfactory. "One such device consists of permanently curved stiff metal plates lconn nected 'together vby "linkage, the plates having transversely extending ribs 4forming anti-skid surfaces. 'Such devices are 'not fully satisfactory because the stili, 'imperfor'ate plates `do not properly vadapt .themselves to 'all conditions encountered in use; moreover, the plates which are purposely made still' .so as to be inflexible are of necessity heavy, cumbersome, and difl'lcult to handle. @ther devices 'such as chains, portable fabric tracks, linked metal plates having pyramidal projections, Wire mesh, etc., have been proposed but none of them has satisfactorily solved the problem.

Ilhave 'found 'that in order 'to satisfactorily enable extri'caltion of an automobile bogged down in mud or 4stuck in snow or ice under -various conditions which may be encountered, a traction device should comprise a plurality of articulated members, each member being of generally sheet form, being foraminous and having at both principal faces projections forming anti-skid surfaces. Each member should be of such strength as to be flexible when laid on a non-planar surface and subjected to the load transmitted 5 through a wheel of an automobile disposed thereon. I nd that light or medium gauge expanded metal is ideally suited to use as a traction device for automobiles. Both principal faces of the expanded metal sheets have projections which form anti-skid surfaces. the sheets are foraininous permitting mud, earth, snow, etc., to penetrate them, and devices made of articulated sheets of expanded metal are easy to manipulate, consume little space, and are light in weight and inexpensive.

Other details, objects and advantages of the invention will become apparent las the following description of a present preferred embodiment thereof proceeds.

In the accompanying drawings I have shown a present preferred embodiment of the invention and have illustrated the use thereof, in which Figure 1 is a plan View of a. traction. dCi/'39 2 consisting of four articulated sheets 4of expanded metal; y

Figure 2 'is an edge View of -the device shown in 'Figure 1 but to enlarged scale, 4the fdevice being shown collapsed; and y Figure 3 is a diagrammatic view illustrating use of the traction fdevice.

Reerring now more particularly to the drawings, there is shown a traction device designated generally .by reference numeral 2 and which -comprises 'sheets Vt of expanded metal articulated -by metal rings l, The expanded metal is preferably of the yguillotine typefconsisting-of stra-nds 5 connected by bonds [5.r The 4'expanded metal is of -`light -or medium gauge and is 'of vsuch strength as 'to be flexible when laid Ion a 'non-planar surface 'and subjected to 'the load A'transmitted through a Wheelf'of Lan automobile disposed thereon as shown in Figure 3.

The sheets oi expanded metal may be of any desired size 'and shape. l iind 'it vconvenient IIto employ sheets 6" or I'8" 'long and of somewhat similar Width. Any number of such `sheets may 4be articulated together to form a traction dev-ice oi desired length. Each individual sheet should be short enough length-Wise of the -device to enable the idevice to readily con-form itself to lirregularities in the surface to which itis applied and also each sheet should be flexible as above stated, whereby much better traction is afforded than When a rigid device is used. The strands and bonds ofthe expanded metal form ideal antiskid projections. As shown in Figure 3, when the device is laid down and employed to extricate an automobile from mud or the like, the projections at one face of the expanded metal dig into the base upon which the device is laid, and the projections at the other face are in anti-skid relation to the automobile tire. The generally diamond-shaped openings in the expanded metal allo-w earth or the like to pass therethrough when the device is laid down, thus facilitating proper positioning of the device and also increasing its eiiiciency, as such a device would under all except the most unusual conditions maintain its position and not slide out from under an automobile Wheel when the wheel is rotated. While the device may be positioned either side up and with either end in the direction in which the vehicle is to be moved, the best eiliciency is obtained by positioning it as shown in Figure 3 in which the vehicle is being moved toward the left. The bonds or bridges of the expanded metal at the lower face thereof extend into the earth, and those at the upper face indent the pneumatic tire, bringing about maximum efficiency of the device.

When not in use the device maybe collapsed as shown in Figure 2, and when so collapsed it occupies very little space. Figure 2 vshows in approximately full-scale a satisfactory device which I have employed. One or two of the devices may conveniently be kept in an automobile for use when required.

With reference to Figure 3, it will be noted that the characteristics of the expanded metal of which the sheets are made are such that the best gripping effect on one side is in the opposite direction to the best gripping eifect on the Opposite side. This makes for maximum eciency when the device is used as shown in Figure 3 since, viewing that figure, the thrust on the device from the wheel is from left to right, and the thrust on the device from the ground is from rig-ht to left.

While I have shown-and described a present preferred embodiment of the invention, it is to `be distinctly understood that the invention isv not limited thereto but may be `otherwise variously embodied within the scope of the following claims.

I .-claim: l

l. A portable traction device adapted to be applied beneath the wheels of vehicles comprising-aplurality of articulated-members, each member being of generally sheet form, being foraminous and having at b othprincipal faces projections forming anti-skid surfaces.

2. A portable traction device adapted to be applied beneath the wheels of Vehicles comprising a plurality of articulated sheets of expanded metal of such strength as to be flexible when laid on a non-planar surface and subjected to the load transmitted through a wheel of an automobile disposed thereon.

. A traction device comprising a plurality of articulated members, each-member being of generally sheet form, being foraminous and having at both principal faces projections forming antiskid surfaces, the projections at each face of a member extending generally at an acute angle to Ithe general plane of the member, the projections at the respective faces extending generally in opposite directions so that when the device is acute angle to the general plane of the sheet, the i laid on the ground with a vehicle Wheel bearing on the upper surface of said member and with the member arranged with the projections eX- tending generally parallel to the plane of the wheel the generally upwardly extending projections most eifectively oppose slippage of the wheel relatively to the member when the wheel is turned in one vdirection and the generally downwardly extending projections most effectively oppose Y movement of the member along the ground in the Idirection .in which the force exerted by the Wheel tends to move it when the wheel is turned in said direction.

4. A `traction device comprising a plurality of articulatedwsheets of expanded metal which' can `be vfolded 'into compact form when not in use, the projecting portions of the expanded metal at each face of a sheet extending generally at an projections at the respective faces extending generally in opposite directions so that when theV device is laid onthe ground with a vehicle wheel bearing on the upper surface ofsaid sheet and with the sheetA arranged v with the projections extending generally parallel to the plane of the wheel the generally upwardly extending projections most effectively oppose slippage of the wheel n REFERENCES Yerrer) The following references are of'record in the ille-of this patent:

UNITED STATES PATENTS Number Name Date 1,324,291 Austen Dec. 9, 19,19 2,243,723 YIench May 271941 Y 2,346,477 AEderer Apr. 11, 1944 2,406,557 

